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Landings

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[ Intro ] [ Prereq ] [ Preparation ] [ CRW Canopies ] [ Landing Techniques ] [ Weather ] [ Accuracy ] [ Other Scenarios ]

Introduction

     Great CRW parachute landings are not just a function of your final approach speed and flaring technique. They begin well before you even get into the aircraft. Hence, it is important to prepare for your landings on each jump. Also, given that the landing performance of a CRW specific canopy is not as good as standard elliptical and 9 cell canopies, it is important to spend a little time preparing for and learning about your first & subsequent CRW canopy landings. The focus should be maintained on every jump.


Prerequisites

     You can and should learn most of the skills you require to land a CRW parachute on other canopies prior to taking up CRW. This means that you will only need to fine tune what you already know when you start jumping CRW parachutes.

     What should you know? The obvious thing is how to fly a parachute. You should have understanding and experience in all control inputs (risers, toggles, harness), all flight configurations (full drive to dynamic and static stalls), affect of flight in turbulence, various landing approaches (full drive straight in, deep brake, cross wind, keyhole), flight in traffic, etc. You should also have a basic understanding of weather (wind), spotting, and accuracy.


Preparation

     Pre jump preparation is vitally important to maximise your safety and enjoyment on each and every jump. What you know before you exit an aircraft will determine where you land, what conditions you land in, and the level of difficulty and safety of the landing area. These factors will also determine what technique you have to use for the landing area. For example, if you have a poor spot in gusting wind conditions, you may have to do a deep brake, vertical approach into a tight, rocky, uneven landing area on the lee (downwind) side of a hill. As far fetched as this may sound, why put yourself into that position. You should have a plan in your head for this and every other eventuality so that you know what to do prior to getting into that situation. It is also good to know the performance envelope of your equipment so that if you do end up having to modify your landing technique, you know how to do it safely. In contrast to the desperate scenario mentioned above, a well prepared jumper will end up swooping onto an open field free of obstacles and other dangers. 

     There are many factors to consider which may seem overwhelming. But with a little practice the preparation can become very quick and efficient. So what should you know before you board the aircraft:

  • wind conditions. You need to know strength, direction, and variability. For CRW, you need to know these from exit height to landing as it will affect your performance on the jump, your safety, and the spot. These can be ascertained from a variety of sources including:
    • wind socks or streamers.
    • meteorological reports.
    • feedback from jumpers on previous loads.
    • data from GPS systems and aircraft speed indicators.
    • information from pilots (your jump pilot as well as any other aircraft in the area).
    • information from aviation information services.
    • movement of land features such as open water, trees, and grass.
    • movement of smoke from chimneys and fires, and airborne dust.
  • topography. Trying to land on the lee (downwind) side of a hill that is full of deep rabbit holes is not a palatable situation. Most drop zones have aerial maps showing all relevant features and hazards as well as appropriate landing areas. You should use this map to determine:
    • what the main landing areas are.
    • alternate landing areas.
    • hazards.
    • distance to drop zone from various landmarks (if you know your glide ratio and this distance, you will be able to determine whether you'll make it back or not).
    • steepness of all proposed landing areas.
  • local hazards. These can include power lines, trees, barbed wire fences, rough terrain (uneven surface that could cause broken limbs), military firing ranges, prisons, alligator farms, crazy neighbours, moving water, sewerage treatment plants, etc.
  • local airspace rules and regulations. Parachutists should amicably and fairly share the airspace with other airspace users. Local safety rules and regulations should be adhered to. This is primarily for safety reasons. But also to maintain a friendly and cooperative atmosphere so that we can all enjoy our favourite aviation activities.
  • local & general etiquette. This includes:
    • the intended landing zones for students, intermediate, and advanced jumpers.
    • proposed landing circuits (left versus right, flight paths over certain landmarks, etc). You should only go against the planned landing pattern if your safety or the safety of others will be compromised.
    • avoiding flight directly over runways at certain altitudes.
    • avoiding exit over or flight in airfield circuit pattern areas.
    • maintain awareness of other aviation users (including other parachutists).
    • which neighbouring properties to avoid on the account of disputes and other issues.
    • permission to perform hook turn landings.
    • low person has right of way.
    • plan for person with highest wing loading to land first.
    • high person should not spiral into the airspace of lower persons. They should stay high. Especially without thoroughly checking the area around and below for other canopy traffic.
    • CRW groups should land together if they are not likely to make it back to the intended DZ (after poor spots, major heading changes, emergencies, etc).

Peculiarities of CRW & CRW Canopies

     There are a number of categories of canopy designs available in the market today. Included amongst these are tandem, elliptical, cross braced, hybrids, rectangular, round, reserve (7 cell rectangular), 9 cell student, BASE, accuracy, and CRW. Within each of these categories is a wide range of aerodynamic characteristics that need to be taken into account. Most contemporary skydivers are brought up on 9 cell and elliptical canopies and they are unfamiliar with the flight characteristics of 7 cell canopies. As a result, they tend to use the same flying technique when they are first confronted with a 7 cell canopy. This can be dangerous. Can you imagine flying a jumbo jet the same way that you fly an aerobatic aircraft?

     So what is different about CRW canopies? Compared to standard ellipticals:

  • most CRW canopies are 7 cells.
  • they are short lined.
  • they often have continuous centre A lines and sometimes continuous outer A lines.
  • they have a higher descent rate in ALL brake configurations.
  • they have a lower glide ratio.
  • their stall point is easier to attain. You can induce an accelerated stall if you transition from high speed riser approach to dropping the risers and aggressively inducing a deep toggle flare.
  • their planing range (distance of flare) is less.
  • their pilot chutes and bridles are usually fully retracted.
  • there is less flaring potential if transitioning from a deep braked approach to a full flare.

     All this means that a CRW canopy does not perform as well as a standard elliptical canopy when comparing general flying characteristics. You should take extra care when flying a CRW canopy. On your first jump, brake off higher and practice flaring, planing, stalls and stall recovery, and use of all your control inputs. If you follow a few simple rules, you wont have a problem. If you brake a few simple rules. . . . . .

     If you are wearing large amounts of weight that is tertiary mounted, your landing safety may be compromised a little. In particular, when making a running landing without full flaring ability, your weights will tend to drag your body forward and cause you to overbalance and fall forward. You may have to use the option of cutting away the weights on each jump. Be very aware of where you are doing this if you pursue this option.


Landing Techniques

     Assuming you have spotted well and will comfortably make your intended landing area, the steps for a safer landing are:

Setup For Final Approach: ensure the area around you is clear of traffic and that you will not hit anyone when performing the manoeuvres discussed in this section. Choose a landing point and a flight path that will get you there (allowing for wind, performance and flying characteristics of your canopy, traffic, and your intended technique). Plan to land into the wind is you will be able to generate the most lift in this direction.

Speed Buildup: What does this mean? The speed that we want to eventually maximise is the forward speed of the canopy in its final planing (or flaring) stage. Speed equals lift. The greater your forward speed, the greater the lift you can generate and the better your flaring capabilities on landing. This obviously assumes sufficient space. You will not be able to do this in a tight landing area. To generate this forward speed during planing, you need to utilise your only available form of energy, gravity. So the cycle of speed generation begins with a sudden and sustained increase in descent rate until an equilibrium is attained where the canopy is fully pressurised (the airfoil is rigid and properly shaped), the suspension lines are under full tension, and the canopy and suspended load are descending at a faster rate.

     There are a number of ways to generate this speed increase on parachutes:

  • straight in approach using both front risers. Because you have less flight dimensions to control using this technique, this is one of the safer methods possible. This means that your heading is set before you begin your manoeuvre. It is also easier to visualise and control the descent rate in a controlled manner by adjusting your front riser input as you descend. Remember to maintain grips on your toggles so that you can flare out at the appropriate height. Another method used by some is to make a deep braked approach, transition rapidly to full drive and allow the canopy to surge forward, and then flare out a landing. Although it is great to have a number of techniques in your repertoire, I prefer not to teach or use this technique as there are too many radical changes in descent rate and forward speed to close to the ground.
  • carving approach. This method involves a controlled turn onto the intended landing heading from any angle, usually somewhere between 45 and 180 degrees off intended landing heading. This can be done a number of ways and it depends on what your desired result is. Often the initial input is dramatic and the release of the input is controlled which means that you may have to allow for lag and momentum in the controls. This means you will have to release the input before you achieve the desired heading.
    • one front riser pulled down, all other control inputs at full drive.
    • one front riser pulled down more than the other.
    • one toggle pulled down. Obviously this technique does not work for both toggles as you will actually decrease the descent rate and forward speed.

    You can also vary the amount you input on each riser to alter your heading as you descend. This allows for a combination of direction and descent rate control.

  • hook turn. You can perform either a front riser or toggle hook turn. The toggle hook turn is the most common method used. This is due to the fact that lesser experienced parachutists are inexperienced in the use of their risers. Many experienced parachutists like to use this method too. The main thing to be careful of is the height you initiate the turn from.  Do it too low and you will either be pendulum swinging through the ground or you will have to flare yourself "out of the corner". Flaring too early and too rapidly reduces you planing and flaring potential immensely. It is harder to judge the perfect height to initiate a hook turn and the difficulty to recover easily and accurately is higher.
  • snap. This is usually a rapid toggle input of around 45 to135 degrees.
  • hybrid. Their are many possibilities if you combine several of the control inputs either together or in a logical sequence. For example, a 180 degree toggle hook turn followed by a double front riser straight in approach. Why would you do something like this? The initial 180 toggle hook turn will give you a rapid increase in descent rate and will take some tension off your suspension lines prior to the parachutist swinging through the pendulum. With the reduced tension, it is easier (takes less effort and energy) to gain maximum front riser input. Here you maintain the descent rate until it is time for your to transition to the flare. Just beware of line tension release. The less tension you have, the less efficient your wing will fly as it is not a well formed and rigid surface anymore.

     The amount that you pull down on any of your control inputs will determine the increase in speed. Basically, the more you pull them down, the faster you will go.

     When first starting out, do this higher until you learn what height is consumed during the manoeuvre. NEVER execute a speed increase at low altitudes. DON'T DO LOW HOOK TURNS. You should also be vigilant about maintaining grips on your toggles so that you can flare after increasing the descent rate.

The Transition - Efficient Canopy Flight

     This is the period of change from high vertical descent to planing out. The wing performs most efficiently when there is minimal distortion to its airfoil shape and the airflow around it. The more dramatic the change of control inputs, the greater the disturbances. Hence, you should aim for a smooth transition.

     This is best explained using one of the scenarios from the speed build up section above. Lets look at the hybrid example. If you really snap the 180, you are more likely to suffer induced line twists, suspension line de-tensioning with resulting partial canopy depressurisation (the suspended load pendulum swings and momentarily goes back into freefall), and if you maintain this position the canopy wants to get back to equilibrium - which is the flight characteristics you started with. The better option is to give a toggle input that is a balance between maximum input and avoiding the pendulum & de-tensioning affect. Prior to the pendulum affect you should commence front riser input. The initial input can be quick. As you straighten out and approach a suitable height to begin your transition, smoothly and consistently let off front riser pressure. The objective is to create a curved flight path, not a dramatic 90 degree change from vertical descent to horizontal. When you have let off all front riser pressure, gradually introduce toggle input. Again, this should be smooth and consistent, not a rapid stab of the brakes.

     Once you can consistently perform this technique, you can introduce a transition from front risers to rear risers, and then to toggles if required.

     The key thing to remember is make it smooth, not dramatic.

     As far as the heights that you should initiate the turns, and transitions, they are different for different airfoils, wing loadings, weather conditions, altitudes, temperatures, pressures, canopy age, line trim, etc, etc. Hence, I can only suggest the following:

  • watch other people using similar equipment to see what techniques they use and the results of their inputs.
  • talk to other parachutists. Remember to use their information as a guide only.
  • practice up high. I VERY STRONGLY recommend the non contact CRW canopy exercises to include some exercises that will assist with landing skills.
  • start with straight in approaches and commence a little higher than on a standard elliptical canopy.
  • build up your skills in a logical order and do not introduce too many new skills at once. The Japanese were notorious for their mass manufacturing technologies. There quality and repeatability is due to SPC (statistical process control). In layman's terms, they monitored and controlled every one of the inputs to their processes. When they introduced new variables, they tested each one by one. Their outputs were very repeatable and successful. You should build and maintain your parachuting skills repertoire in a similar manner. Build your skills one by one, keep an eye on them whenever you use them.

Weather & Altitude Considerations

     The ideal landing conditions include:

  • constant 5 to 15 knot unidirectional breeze. No gusts, no excess strength, no direction changes.
  • flat landing area with no obstacles.
  • soft, smooth landing area.
  • sea level elevation.

Altitude

     As altitude increases, the air density & resistance decreases. This basically means that as the elevation of your landing zone increases, your flaring ability decreases. You land harder as you get higher.

Wind - Relative Motion of Air Masses

     CRW parachutists need to consider wind direction, strength and variability, and all forms & sources of thermal activity in their landing preparation. Excessive variability can be dangerous, especially when performing "radical" manoeuvres for landing. Jumpers should not attempt to land formations in high or gusty winds, high density altitudes, or high field elevations either. In fact, all CRW activity should cease when you encounter moderate to severe turbulence.

Thermals

     Sources of thermal activity include: paved surfaces, plowed fields, and buildings. Depending on the conditions at the time, these thermals may contribute to the development of CN clouds. These thermals will be affected by prevailing winds. Avoid flying at low altitudes downwind of thermal sources.

Humidity / Rain

    


Accuracy

    


Other Landing Scenarios

     It would be pertinent to start this section with this advice: DO NOT ATTEMPT ANY OF THE FOLLOWING LANDING SCENARIOS. Try to avoid them in the first place.

Planned Bi-Plane: The landing of canopy formations should be attempted by only those with a high level of CRW proficiency.

Dual Canopies - Single Person:

Main / Reserve Entanglements:

Wraps:

Entanglements:

Other Formations:


 

 

Following are notes & other ideas relevant to this section that require further development. Please ignore.

  1. Flight & landing Patterns. It is important to follow the dive plan throughout the descent. This includes landings.
    • Break off and landing procedures: 
      • a. Approaches and docking should stop no lower than 2,500 feet AGL.
      • b. Formation pilots should avoid all obstacles, including suspected areas of thermal activity, such as paved surfaces, plowed fields, buildings, etc.
      • d. Break off for landing should take place no lower than 2,500 feet AGL, because of the danger of entanglement at break off time.

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